<< Click to Display Table of Contents >> Navigation:  Help Content > Basic Module > Feature Extraction > Basic module -  Feature Extraction - Multi Temporal Features

Purpose

 

SAR intensity data can be used to derive multitemporal features based on first-order statistics. Depending on the target product, these features enable the detection and extraction of structures or temporal changes, which can then be used for segmentation and/or classification. The combination of these features can further enhance the description of the Area of Interest. The most commonly used Multitemporal Features can be set in the corresponding preference tab in SARscape preferences.

 

Technical Note

 

The temporal features are extracted from coregistered or geocoded time-series Intensity images.

 

The "Input file list" is automatically sorted in chronological order before generating the required products.

 

Input Files

 

Input file list

Input file list of the coregistered or geocoded (_geo) multitemporal Intensity data (values have to be in linear scale). This file list is mandatory.

 

Parameters - Principal Parameters

 

By setting this flag the output pixel value represents the average calculated from all input data.

 

Std        

By setting this flag the output pixel value represents the standard deviation calculated from all input data.

 

Median        

By setting this flag the output pixel value represents the median value (the central value in the ordered series) calculated from all input data.

 

Gradient        

By setting this flag the output pixel value represents the maximum absolute variation between consecutive acquisition dates. The sign of the variation (i.e. increment or decrement) is not taken into account. This file is not generated when the "dB" flag is checked.

 

Max

By setting this flag the output pixel represents the maximum value extracted from all input data.

 

Min        

By setting this flag the output pixel represents the minimum value extracted from all input data.

 

Span Difference        

By setting this flag the output pixel represents the difference between the maximum value and the minimum value of all input data. This file is not generated when the "dB" flag is checked.

 

Max Increment

By setting this flag the output pixel value represents the maximum increment between consecutive acquisition dates. This file is not generated when the "dB" flag is checked.

 

Max Decrement

By setting this flag the output pixel value represents the maximum decrement between consecutive acquisition dates. This file is not generated when the "dB" flag is checked.

 

Span Ratio        

By setting this flag the output pixel represents the ratio calculated between the maximum value and the minimum value of all input data.

 

Max Ratio

By setting this flag the output pixel represents the maximum value (max backscatter increment) among all ratios calculated between consecutive acquisition dates.

 

Min Ratio

By setting this flag the output pixel represents the minimum value (max backscatter decrement) among all ratios calculated between consecutive acquisition dates.

 

MuSigma

By setting this flag the output pixel represents the mean/standard deviation ratio.

 

Coefficient of Variation        

By setting this flag the output pixel represents the standard deviation/mean ratio.

 

Generate Dates

By setting this flag the dates corresponding to minimum and maximum values are provided (refer to the Technical Note for details).

 

Mode        

By setting this flag the output pixel value represents the mode value (the value which appears more often in the input series) calculated from all input data.

 

Make cmg RGB

By setting this flag an RGB image containing the Coefficient of Variation, the Minimum and the Gradient will be generated.

 

Generate Shape

By setting this flag the output shape file/s, with the displacement temporal evolution, are generated.

 

Parameters - Global

 

It brings to the general section of the Preferences parameters. Any modified value will be used and stored for further processing sessions.

 

Parameters - Other Parameters

 

It brings to the general section of the Preferences parameters. Any modified value will be used and stored for further processing sessions.

 

Output Files

 

Output Root Name

Output root name of the selected feature(s). This root name is mandatory.

 

_spanD        

Span difference and associated header files (.sml, .hdr).

 

_spanR        

Span ratio and associated header files (.sml, .hdr).

 

_cov

Coefficient of variation and corresponding header files (.sml, .hdr).

 

_mea        

Mean image and associated header files (.sml, .hdr).

 

_med        

Median image and associated header files (.sml, .hdr).

 

_max                

Maximum value and associated header files (.sml, .hdr).

 

_max_Date            

For each Pixel, the date of the Maximum value is assigned. Associated header files (.sml, .hdr) are also created.

 

_min                

Minimum value and associated header files (.sml, .hdr).

 

_min_Date        

For each Pixel, the date of the Minimum value is assigned. Associated header files (.sml, .hdr) are also created.

 

muSigma        

MuSigma value and associated header files (.sml, .hdr).

 

_grad        

Gradient image and associated header files (.sml, .hdr).

 

_maxD        

Maximum decrement and associated header files (.sml, .hdr).

 

_maxD_Date        

For each Pixel, the date range of the Maximum Decrement value is assigned. Associated header files (.sml, .hdr) are also created.

 

_maxI        

Maximum increment and associated header files (.sml, .hdr).

 

_maxI_Date        

For each Pixel, the date range of the Maximum Increment value is assigned. Associated header files (.sml, .hdr) are also created.

 

_maxR        

Maximum ratio and associated header files (.sml, .hdr).

 

_minR        

Minimum ratio and associated header files (.sml, .hdr).

 

_std        

Standard deviation and associated header files (.sml, .hdr).

 

_CovMin_grad_rgb.tif

TIFF image of the assembled RGB imageand associated header files (.hdr).

 

Details specific to the Units of Measure and Nomenclature of the output products can be found in the Data Format section.

 

General Functions

 

Exec

The processing step is executed.

 

Store Batch        

The processing step is stored in the batch list. The Batch Browser button allows to load the batch processing list.

 

Close        

The window will be closed.

 

Help

Specific help document section.

 

 

Specific Function(s)

 

None.

 

See Also

 

Task, SARscapeBatch object, SARscapeBatch script example

 

References

 

None.